SummaryA reversed -phase HPLC method with UV detection for determination of chlorhexidine in gingival crevicular fluid (GCF) was optimized and validated, using chlorpheniramine as an internal standard. The chromatographic separation was performed on Discovery C18 HPLC column with 0.01 mol L -1 phosphate buffer (pH=3.0), triethylamine and acetonitrile (66:1:33, V/V/V), as mobile phase. Under the optimized HPLC conditions, linearity was obtained in the range of 0.5-5.0 µg mL -1 with LOD 0.07 µg mL -1 and LLOQ 0.5 µg mL -1 . The described method can be successfully applied for determination of chlorhexidine concentrations in GCF obtained from patients with chronic periodontal disease treated with PerioChip TM .
In 2015, in Republic of North Macedonia, a new law for narcotics has been adopted, where the changes include legal cultivation of cannabis for medicinal use as well as legal production of cannabis extracts for medicinal use. In order to gain high quality of cannabis and cannabis products for medicinal use and to meet some quality standards that will guarantee consistency, traceability and continuous quality of the product, it is necessary to implement Quality Systems. Good quality system is ISO standard system but for cannabis for medicinal use, GACP, GMP and GLC standards are used more often. Production of cannabis for medicinal use consists of: process of cultivation where GACP standards are applicable, primary processing where GMP standards are the most important and quality control of final product regulated with GLP standard.
In this review, explanation of these standards as well as overview of modes of their implementation has been made.
Keywords: GxP, GMP, GACP, GLP
Oral contraceptives are pharmaceutical formulations containing an estrogen in a small amount and a synthetic progestin in 5-30 times bigger amount. A sensitive, accurate and rapid method for determination of active compounds is required. We have developed HPLC methods for determination of ethinylestradiol (EED) and levonorgestrel (LNG) in commercially available tablets. Chromatographic separation was performed on a Purospher® STAR RP-18e reversed-phase column (150 X 4.0 mm I.D.; particle size 5 µm) in an isocratic mode with a mobile phase constituted of 47% acetonitrile: 53% water (V/V) for both methods. The elution was carried out at a flow rate of 1.50 ml /min. All analyses were performed at room temperature (24 +/- 2°C). In the HPLC method with UV detection (internal standard method) both compounds were detected at 215 nm. Drospirenone was used as an internal standard. In HPLC method with UV/fluorescence detection (external standard method) LNG was monitored at 242 nm, while EED was detected with fluorescence detector at 310 nm (excitation 285 nm). The methods’ performances were fully validated by a determination of linearity, reproducibility, accuracy and sensitivity. Both methods were applied for determination of Uniformity of Dosage Units. The results obtained with both methods were highly comparable. However, the HPLC method with UV/ fluorescence detection has showed superior sensitivity for EED indicated by 83 times lower detection limit. HPLC method with UV/ fluorescence detection could be recommended as a method of choice for determination of ethinylestradiol, present at a very low dosage level in low-dose oral contraceptives, that also contain bigger amount of synthetic progestin.
The aim of this work was to develop a single, generally applicable high performance liquid chromatography/diode array detector (HPLC/DAD) method for simultaneous determination of the most frequently used cough and cold active substances and their impurities that would be applicable for a number of possible formulation compositions of cough and cold medicines. The compounds that are separated by the method include eleven active substances: paracetamol, phenylephrine HCl, caffeine, ibuprofen, ascorbic acid, propiphenazone, pheniramine maleate, chlorphenamine maleate, pseudoephedrine HCl, dextromethorphan HBr and cetylpyridinium Cl; five of their impurities: 4-aminophenol, 4-nitrophenol, 4`-chloroacetanilide, chlorphenamine impurity C and ephedrine HCl; and two preservatives: sodium benzoate and propyl parahydroxybenzoate. All 18 compounds were successfully separated on a reversed phase (RP)-HPLC column with superficially porous particles using gradient elution with a very simple mobile phase in 14 minutes with excellent sensitivity and resolution. Method optimization was performed by the design of experiments approach. The proposed method has been validated according to ICH guidelines and proved to be suitable for the simultaneous qualitative and quantitative determination of the selected compounds in different cough and cold dosage forms.
Keywords: cough and cold active substances and impurities, HPLC/DAD, superficially porous particles, core-shell particles, chemometrics, design of experiments
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